Many machines for exercising arms, chests, and backs of users have been developed in recent years. For example, German Patent No. DE 3532444, issued Mar. 19, 1987, discloses an exercise machine having pivotally swinging training arms that reciprocate through active and passive movements with a maximum force capacity greater than the force that can be imparted by the user. It includes a recording device that detects and displays the angle-dependent force exerted by the user.
Exerbotics, LLC has developed a chest press/row machine, as advertised on its exerbotics.com website, having reciprocating pivoted arms that can be selectively powered for either pulling or pushing, and includes means for detecting and displaying the amount of pressure being exerted by the user.
U.S. Pat. No. 7,578,774, issued Aug. 25, 2009, discloses an exercise machine adding a bar that reciprocates vertically op and down, and is powered by a motor to reciprocate at a constant rate, with the capacity of force being applied by the motor being greater titan the press or pull of the user.
Other examples of exercise machines having a drive mechanism driven at a constant rate regardless of the resistive force applied by the user are disclosed in U.S. Pat. No. 6,019,740, issued Feb. 1, 2000, U.S. Pat. No. 4,930,770, issued Jan. 5, 1990, and U.S. Pat. No. 4,919,418, issued Apr. 24, 1990.
None of these prior art disclosures have pivotable hand gaps that allow repositioning of the hands of the user, without releasing the handle, from a position for pushing against movement of exercise arms toward the user to exercise a particular set of muscles and a reversed position of the hands for pulling against movement of exercise arms away from the user to exercise a different set of muscles. Universally pivotable hand grips are disclosed in the prior an, such as in U.S. Pat. No. 5,344,374, issued Sep. 6, 1994, U.S. Pat. No. 5,407,405, issued Apr. 18, 1995, and U.S. Patent Publication No. 2004/0082448, published Apr. 29, 2004. However, none of these universally pivotable hand grip disclosures are for the purpose of alternately positioning the hands of the user for applying resistance to an exercise arm moving toward the user for exercising one set of muscles and positioning the hands of the user for applying resistance to an exercise arm moving away from the user for exercising a different set of muscles.
Further, there is no known disclosure in the prior art of controlling the rate of reciprocation of said arms during a set of reciprocations in a pattern, selected by the user, of incrementally increasing rates of reciprocation during sequential repetitions of a set of repetitions to simulate the fatigue factor occurring when a user is exercising with free weights.